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speculation; thinking; meditation
思索にふけって時を忘れた。
I lost track of time, lost in thought.
深い思索の末に新たな解決策を見出した。
After deep reflection, a new solution was found.
哲学者は日常の喧騒を離れ、孤独の中で思索を深めた。
The philosopher left the noise of everyday life and deepened his contemplation in solitude.